Analysis of spatio-temporal changes in annual and seasonal precipitation variability in South America-Chile and related ocean–atmosphere circulation patterns

Establishing relationships between coupled ocean–atmospheric patterns and precipitation accumulation is important to describe and predict spatio-temporal variability on annual or seasonal scales, and also to evaluate how this variability is influenced by global warming. The objective of this study was to examine the leading modes of interannual and seasonal (summer, autumn, winter, and spring) precipitation variability in South America-Chile, and their significant relationship to seasonally aggregated gridded data and climatic indices. Applying exhaustive data quality control measures to data from 238 rain gauges with different lengths of records between 1893 and 2013, a new data set was created with the objective of obtaining reliable records for further analysis. A comprehensive analysis through empirical orthogonal functions (EOF) allowed for determination of the leading modes of annual and seasonal precipitation and their main spatial patterns for the whole country. The percentage of explained variance in the relationship between seasonally aggregated indices and the leading modes of precipitation confirmed that most of the interannual and winter precipitation variability in Chile is linked to the seasonal aggregation of El Nino Southern Oscillation (ENSO). The leading modes of summer, autumn, and spring precipitation were mostly linked to seasonal aggregations of the Madden and Julian Oscillation (MJO), and the Antarctic Oscillation (AAO)

Improving Operational Short- to Medium-Range (SR2MR) Streamflow Forecasts in the Upper Zambezi Basin and Its Sub-Basins Using Variational Ensemble Forecasting

The combination of Hydrological Models and high-resolution Satellite Precipitation Products (SPPs) or regional Climatological Models (RCMs), has provided the means to establish baselines for the quantification, propagation, and reduction in hydrological uncertainty when generating streamflow forecasts. This study aimed to improve operational real-time streamflow forecasts for the Upper Zambezi River Basin (UZRB), in Africa, utilizing the novel Variational Ensemble Forecasting (VEF) approach. In this regard, we describe and discuss the main steps required to implement, calibrate, and validate an operational hydrologic forecasting system (HFS) using VEF and Hydrologic Processing Strategies (HPS). The operational HFS was constructed to monitor daily streamflow and forecast them up to eight days in the future. The forecasting process called short- to medium-range (SR2MR) streamflow forecasting was implemented using real-time rainfall data from three Satellite Precipitation Products or SPPs (The real-time TRMM Multisatellite Precipitation Analysis TMPA-RT, the NOAA CPC Morphing Technique CMORPH, and the Precipitation Estimation from Remotely Sensed data using Artificial Neural Networks, PERSIANN) and rainfall forecasts from the Global Forecasting System (GFS). The hydrologic preprocessing (HPR) strategy considered using all raw and bias corrected rainfall estimates to calibrate three distributed hydrological models (HYMOD_DS, HBV_DS, and VIC 4.2.b). The hydrologic processing (HP) strategy considered using all optimal parameter sets estimated during the calibration process to increase the number of ensembles available for operational forecasting. Finally, inference-based approaches were evaluated during the application of a hydrological postprocessing (HPP) strategy. The final evaluation and reduction in uncertainty from multiple sources, i.e., multiple precipitation products, hydrologic models, and optimal parameter sets, was significantly achieved through a fully operational implementation of VEF combined with several HPS. Finally, the main challenges and opportunities associated with operational SR2MR streamflow forecasting using VEF are evaluated and discussed

Mudflow Modeling in the Copiapó Basin, Chile

[EN] Extreme precipitation events that occurred between March 24 and March 26 of 2015 in the region of the Atacama Desert (26-29°S) left around 30 000 victims, being one of the biggest events over the past 50 years, with total a cost of reconstruction of about 1.5 billion dollars. The mudflows which increased during the flashflood inundated much of the city of Copiapó and Tierra Amarilla. This manuscript aims to model the mudflow of March 2015 in the Río Copiapó, specifically in the towns of Copiapó and Tierra Amarilla. The modeling process is performed using the Rapid Mass Movement Simulation Model (RAMMS) that allows modeling the dynamics of the mudflow in two dimensions, only using the topographic features of the modeling domain. Calibration of the model was carried out successfully using data from inundation heights captured around the city after the 2015 event. A detailed analysis of the hydrometeorological event is carried out using satellite images obtained from Multi-satellite Precipitation Analysis (TMPA), and pluviometric and hydrographic data available in the Copiapó River basin. The simulation of the flood is reproduced with maps of inundation heights associated with two modeling scenarios. The maximum flood heights are ultimately used for developing risk maps at both sites. According to our results, the RAMMS model is an appropriate tool for modeling mudflow and mapping flood risk to improve hydrological risk management in arid and semiarid basins of Chile[ES] Los eventos extremos de precipitación intensa que se produjeron entre el 24 y 26 de marzo de 2015 en la región del Desierto de Atacama (26-29°S), en el Norte de Chile, dejaron alrededor de 30 000 damnificados, siendo uno de los eventos de mayores magnitudes de los últimos 50 años, y que tuvo un costo de reconstrucción de alrededor de $1.5 billones de dólares. Los flujos de detritos que se incrementaron durante la crecida inundaron gran parte de las ciudades de Copiapó y Tierra Amarilla. Este manuscrito tiene por objetivo modelar la crecida aluvional de marzo de 2015 en la cuenca del Río Copiapó, específicamente en las localidades de Copiapó y Tierra Amarilla. La modelación se lleva a cabo utilizando el modelo Rapid Mass Movement Simulation (RAMMS) que permite modelar la dinámica de la crecida aluvional en dos dimensiones, utilizando las características topográficas de los dominios de modelación. La calibración del modelo fue llevada a cabo satisfactoriamente utilizando datos de alturas capturados en terreno después de la crecida del año 2015. Un análisis detallado del evento hidrometeorológico es llevado a cabo utilizando imágenes satelitales obtenidas desde Multi-satellite Precipitation Analysis (TMPA), así como datos pluviométricos e hidrográficos disponibles en la cuenca del Río Copiapó. La simulación de la crecida es reproducida con mapas de alturas de inundación asociados a dos escenarios de modelación. Las alturas máximas de inundación son finalmente utilizadas para el desarrollo de mapas de riesgos en ambas localidades. De acuerdo a nuestros resultados, el modelo RAMMS es una herramienta apropiada para modelar crecidas aluvionales y elaborar mapas de riesgos de inundación para mejorar la gestión de riesgos hidrológicos en cuencas áridas y semiáridas de Chile.Los autores de este manuscrito agradecen el financiamiento proporcionado por La Fundación Centro Nacional del Medio Ambiente de Chile (CENMA) para llevar a cabo este estudio. Adicionalmente, se agradece la contribución de datos de alturas de inundación proporcionados por Tatiana Izquierdo (académica de la Universidad de Atacama) los cuales permitieron la calibración del modelo RAMMS.Valdés-Pineda, R.; Valdés, JB.; García-Chevesich, P. (2017). Modelación de Crecidas Aluvionales en la Cuenca del Río Copiapó, Chile. Ingeniería del Agua. 21(2):135-152. doi:10.4995/ia.2017.7366.SWORD135152212Abrams, M. 2000. The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER): data products for the high spatial resolution imager on NASA's Terra platform. International Journal of Remote sensing, 21(5), 847-859. https://doi.org/10.1080/014311600210326Barrett, B. S., Campos, D. A., Veloso, J. V., Rondanelli, R. 2016. Extreme temperature and precipitation events in March 2015 in central and northern Chile. Journal of Geophysical Research: Atmospheres, 121(9): 4563-4580. https://doi.org/10.1002/2016jd024835Bontemps, S., Defourny, P., Bogaert, E. V., Arino, O., Kalogirou, V., Perez, J. R. 2011. GLOBCOVER 2009-Products description and validation report.Bozkurt, D., Rondanelli, R., Garreaud, R., Arriagada, A. 2016. Impact of warmer eastern tropical Pacific SST on the March 2015 Atacama floods. Monthly Weather Review, 144(11), 4441-4460. https://doi.org/10.1175/MWR-D-16-0041.1Christen, M., Bartelt, P., Kowalski, J., Stoffel, L. 2008. Calculation of dense snow avalanches in three-dimensional terrain with the numerical simulation program RAMMS. In Proceedings Whistler 2008 International Snow Science Workshop, September 21-27, 2008 (p. 709).Christen, M., Kowalski, J., Bartelt, P. 2010. RAMMS: numerical simulation of dense snow avalanches in three-dimensional terrain. Cold Regions Science and Technology, 63(1), 1-14. https://doi.org/10.1016/j.coldregions.2010.04.005Ferrando, R., Fuentes, F., Coloma, F., Merino. 2015. Efectos Geológicos del Evento Meteorológico del 24 y 25 de marzo De 2015: Fotointerpretación y Reconocimiento en Terreno del Efecto de Aluviones e Inundaciones en las zonas de Tierra Amarilla y Nantoco: Zona de Inundación y zonas propuestas para Evacuación, Campamento y Acopio. SERNAGIOMIN.Izquierdo, T., Abad, M. Bernárdez, E. 2016. Catastrophic flooding caused by a mudflow in the urban area of Copiapó (Atacama Desert, northern Chile). International Conference on Urban Risks.MOP-DGA, C. I. 2004. Diagnóstico y clasificación de los cursos y cuerpos de agua según objetivo de calidad. Cuenca Quebrada de Tarapacá. Santiago, Chile.Naranjo, J. A., Olea-Encina, P. 2015. Descargas aluviales durante la tormenta del desierto de Atacama en marzo de 2015, Chile. SERNAGIOMIN.Pizarro-Tapia, R., Valdés-Pineda, R., Olivares, C., González, P. A. 2014. Development of Upstream Data-Input Models to Estimate Downstream Peak Flow in Two Mediterranean River Basins of Chile. Open Journal of Modern Hydrology, 4(4), 132-143. https://doi.org/10.4236/ojmh.2014.44013Quan, L. 2012. Dynamic numerical run-out modeling for quantitative landslide risk assessment. Thesis of University of Twente, ITC, 206:1-237.Raïmat, C., Riera, E., Graf, C., Luis-Fonseca, R., Fañanás, C., Hurlimann Ziegler, M. 2013. Experiencia de la aplicación de RAMMS para la modelización de flujo tras la aplicación de las soluciones flexibles VX en el barranc de Portainé. In VIII Simposio Nacional sobre Taludes y Laderas Inestables, 1131-1144. Centre Internacional de Mètodes Numèrics en Enginyeria (CIMNE).Tachikawa, T., Hato, M., Kaku, M., Iwasaki, A. 2011. Characteristics of ASTER GDEM version 2. In Geoscience and Remote Sensing Symposium (IGARSS), 2011 IEEE International, 3657-3660. https://doi.org/10.1109/IGARSS.2011.6050017Valdés-Pineda, R., Valdés, J. B., Diaz, H. F., Pizarro-Tapia, R. 2016. Analysis of spatio-temporal changes in annual and seasonal precipitation variability in South America-Chile and related ocean-atmosphere circulation patterns. International Journal of Climatology, 36(8), 2979-3001. https://doi.org/10.1002/joc.4532Valdés-Pineda, R., Cañón, J., Valdés, J. B. 2017. Multi-decadal 40-to 60-year cycles of precipitation variability in Chile (South America) and their relationship to the AMO and PDO signals. Journal of Hydrology. (In Press). http://doi.org/10.1016/j.jhydrol.2017.01.03

WEBSEIDF: A web-based system for the estimation of IDF curves in Central Chile

The lack of reliable continuous rainfall records can exacerbate the negative impact of extreme storm events. The inability to describe the continuous characteristics of rainfall from storm events increases the likelihood that the design of hydraulic structures will be inadequate. To mitigate extreme storm impacts and improve water governance at the catchment scale, it is vital to improve the availability of data and the array of tools used to model and forecast hydrological processes. In this paper, we describe and discuss the implementation of a web-based system for the estimation of intensity–duration–frequency (IDF) curves (WEBSEIDF) in Chile. The web platform was constructed using records from 47 pluviographic gauges available in central Chile (30–40° S), with at least 15 years of reliable records. IDF curves can be generated for durations ranging from 15 min to 24 h. In addition, the extrapolation of rainfall intensity from pluviograph to pluviometric gauges (i.e., 24-h rainfall accumulation) can be carried out using the storm index (SI) method. IDF curves can also be generated for any spatial location within central Chile using the ordinary Kriging method. These procedures allow the generation of numerical and graphical displays of IDF curves, for any selected spatial location, and for any combination of probability distribution function (PDF), parameter estimation method, and type of IDF model. One of the major advantages of WEBSEIDF is the flexibility of its database, which can be easily modified and saved to generate IDF curves under user-defined scenarios, that is, changing climate conditions. The implementation and validation of WEBSEIDF serves as a decision support system, providing an important tool for improving the ability of the Chilean government to mitigate the impact of extreme hydrologic events in central Chile. The system is freely available for students, researchers, and other relevant professionals, to improve technical decisions of public and private institutions

Analysis of spatio-temporal changes in annual and seasonal precipitation variability in South America-Chile and related ocean–atmosphere circulation patterns

Establishing relationships between coupled ocean–atmospheric patterns and precipitation accumulation is important to describe and predict spatio-temporal variability on annual or seasonal scales, and also to evaluate how this variability is influenced by global warming. The objective of this study was to examine the leading modes of interannual and seasonal (summer, autumn, winter, and spring) precipitation variability in South America-Chile, and their significant relationship to seasonally aggregated gridded data and climatic indices. Applying exhaustive data quality control measures to data from 238 rain gauges with different lengths of records between 1893 and 2013, a new data set was created with the objective of obtaining reliable records for further analysis. A comprehensive analysis through empirical orthogonal functions (EOF) allowed for determination of the leading modes of annual and seasonal precipitation and their main spatial patterns for the whole country. The percentage of explained variance in the relationship between seasonally aggregated indices and the leading modes of precipitation confirmed that most of the interannual and winter precipitation variability in Chile is linked to the seasonal aggregation of El Nino Southern Oscillation (ENSO). The leading modes of summer, autumn, and spring precipitation were mostly linked to seasonal aggregations of the Madden and Julian Oscillation (MJO), and the Antarctic Oscillation (AAO)

The First Drying Lake in Chile: Causes and Recovery Options

Located southwest of the city of Santiago (Chile), the Aculeo Lagoon used to be an important body of water, providing environmental, social, and economic services to both locals (mostly drinking water and small-scale agricultural irrigation) and tourists who visited the area for fishing, sailing, and other recreational activities. The lagoon dried completely in May of 2018. The phenomenon has been attributed to the current climatic drought. We implemented and calibrated a surface-groundwater model to evaluate the hydrogeologic causes of the lagoon's disappearance, and to develop feasible solutions. The lagoon's recovery requires a series of urgent actions, including environmental education and significant investment in infrastructure to import water. Ultimately, there are two goals: bringing back historic water levels and ensuring the sustainability of water resources at the catchment scale.Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

The Impact of a Lack of Government Strategies for Sustainable Water Management and Land Use Planning on the Hydrology of Water Bodies: Lessons Learned from the Disappearance of the Aculeo Lagoon in Central Chile

Several studies have focused on why the Aculeo Lagoon in central Chile disappeared, with a recent one concluding that a lack of precipitation was the main cause, bringing tremendous political consequences as it supported the argument that the government is not responsible for this environmental, economic, and social disaster. In this study, we evaluated in detail the socio-economic history of the watershed, the past climate and its effects on the lagoon’s water levels (including precipitation recycling effects), anthropogenic modifications to the lagoon’s water balance, the evolution of water rights and demands, and inaccurate estimates of sustainable groundwater extraction volumes from regional aquifers. This analysis has revealed novel and undisputable evidence that this natural body of water disappeared primarily because of anthropogenic factors (mostly river deviations and aquifer pumping) that, combined with the effects of less than a decade with below-normal precipitation, had a severe impact on this natural lagoon–aquifer system

The Impact of a Lack of Government Strategies for Sustainable Water Management and Land Use Planning on the Hydrology of Water Bodies: Lessons Learned from the Disappearance of the Aculeo Lagoon in Central Chile

Several studies have focused on why the Aculeo Lagoon in central Chile disappeared, with a recent one concluding that a lack of precipitation was the main cause, bringing tremendous political consequences as it supported the argument that the government is not responsible for this environmental, economic, and social disaster. In this study, we evaluated in detail the socio-economic history of the watershed, the past climate and its effects on the lagoon’s water levels (including precipitation recycling effects), anthropogenic modifications to the lagoon’s water balance, the evolution of water rights and demands, and inaccurate estimates of sustainable groundwater extraction volumes from regional aquifers. This analysis has revealed novel and undisputable evidence that this natural body of water disappeared primarily because of anthropogenic factors (mostly river deviations and aquifer pumping) that, combined with the effects of less than a decade with below-normal precipitation, had a severe impact on this natural lagoon–aquifer system

Spatio-temporal trends of precipitation, its aggressiveness and concentration, along the Pacific coast of South America (36–49°S)

<p>Precipitation is the most critical climatic element that directly affects the availability of water resources. The objective of this study was to describe and discuss spatio-temporal patterns of annual precipitation, its aggressiveness, and its concentration along the southwest coast of South America (36°–49°S) from 1930 to 2006. An annual and multi-decadal analysis was applied to 107 sampling stations distributed throughout this region, using the Mann-Kendall test (MK), and the Sampling Uncertainty Analysis (SUA) coupled with Gumbel probability density function (SUA-Gumbel). The analysis revealed positive but not significant trends in annual precipitation and aggressiveness for the region between 36° and 44°S, at least during the last 50 years of the analysed period. However, a significant decrease in annual precipitation and aggressiveness was observed between 44° and 49°S during the same period. The annual concentration of precipitation became slightly more seasonal in the last 50 years within the entire study area.</p

Forest species in the recovery of soils contaminated with copper due to mining activities

La minería es la actividad económica más importante de Chile, la cual causa degradación significativa en las regiones áridas. Los suelos de la Región de Coquimbo han sufrido contaminación metales pesados provenientes de la minería, particularmente cobre. La implementación de medidas, que ayuden a minimizar el impacto ambiental de los relaves mineros, requiere conocer la capacidad de adaptación de especies vegetales ante la degradación de suelos contaminados. El objetivo de este estudio fue determinar y comparar la capacidad de fitoestabilización de especies vegetales nativas y exóticas en áreas degradadas por la actividad minera en la Región de Coquimbo. Las tasas de supervivencia, crecimiento y desarrollo del dosel de 20 especies fueron evaluadas en dos ensayos experimentales. La concentración de Cu se evaluó en tallos y hojas de los árboles y en diferentes profundidades del suelo. Los resultados indicaron que Acacia saligna tiene la mejor capacidad de acumulación de metales pesados (34.8 ppm en hojas y 12.3 ppm en tallos, ambos en suelos sin fertilizar), con tasas de supervivencia mayores de 80 %. Se concluye que A. saligna es la mejor especie para actividades de fitoestabilización en relaves mineros de la Región de Coquimbo